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Helping Unclog the Mail:
After World War II, mail volume grew every year -- doubling between 1946 and 1966. Dependent on federal subsidies, the Post Office couldn't buy enough machines and hire enough employees to keep up. In October 1966, a flood of holiday advertisements and election mailings choked the system.
The Chicago Post Office, the world's largest postal facility at the time, was overwhelmed by mail. It stopped delivering mail for three weeks. Mail overflowed surrounding post offices. Soon, the mail back up was felt across the country. Change was essential.
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